diff options
| -rw-r--r-- | doc/rtd/topics/format.rst | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/doc/rtd/topics/format.rst b/doc/rtd/topics/format.rst index ed87d3ed..436eb00f 100644 --- a/doc/rtd/topics/format.rst +++ b/doc/rtd/topics/format.rst @@ -127,11 +127,11 @@ Begins with: ``#cloud-boothook`` or ``Content-Type: text/cloud-boothook`` when u Part Handler ============ -This is a ``part-handler``. It will be written to a file in ``/var/lib/cloud/data`` based on its filename (which is generated). -This must be python code that contains a ``list_types`` method and a ``handle_type`` method. -Once the section is read the ``list_types`` method will be called. It must return a list of mime-types that this part-handler handles. +This is a ``part-handler``: It contains custom code for either supporting new mime-types in multi-part user data, or overriding the existing handlers for supported mime-types. It will be written to a file in ``/var/lib/cloud/data`` based on its filename (which is generated). +This must be python code that contains a ``list_types`` function and a ``handle_part`` function. +Once the section is read the ``list_types`` method will be called. It must return a list of mime-types that this part-handler handles. Because mime parts are processed in order, a ``part-handler`` part must precede any parts with mime-types it is expected to handle in the same user data. -The ``handle_type`` method must be like: +The ``handle_part`` function must be defined like: .. code-block:: python @@ -141,8 +141,9 @@ The ``handle_type`` method must be like: # filename = the filename of the part (or a generated filename if none is present in mime data) # payload = the parts' content -Cloud-init will then call the ``handle_type`` method once at begin, once per part received, and once at end. -The ``begin`` and ``end`` calls are to allow the part handler to do initialization or teardown. +Cloud-init will then call the ``handle_part`` function once before it handles any parts, once per part received, and once after all parts have been handled. +The ``'__begin__'`` and ``'__end__'`` sentinels allow the part handler to do initialization or teardown before or after +receiving any parts. Begins with: ``#part-handler`` or ``Content-Type: text/part-handler`` when using a MIME archive. |